feat(graphql): implement Node for top level query field

src/graphql/__tests__/__snapshots__/graphqlIntegration-test.js.snap

@@ -246,7 +246,7 @@ enum PostStatus {
 }
 
 # The root query type which gives access points into the data universe.
-type Query {
+type Query implements Node {
   # Fetches an object given its globally unique \`ID\`.
   node(
     # The globally unique \`ID\`.
@@ -319,6 +319,9 @@ type Query {
   # Exposes the root query type nested one level down. This is helpful for Relay 1
   # which can only query top level fields if they are in a particular form.
   query: Query!
+
+  # The root query type must be a \`Node\` to work well with Relay 1 mutations. This just resolves to \`query\`.
+  __id: ID!
 }
 
 input UpdatePersonByEmailInput {

src/graphql/schema/getQueryGQLType.ts

@@ -1,22 +1,29 @@
-import { GraphQLObjectType, GraphQLFieldConfig, GraphQLNonNull } from 'graphql'
+import { GraphQLObjectType, GraphQLFieldConfig, GraphQLNonNull, GraphQLID } from 'graphql'
 import { buildObject, memoize1 } from '../utils'
 import createNodeFieldEntry from './node/createNodeFieldEntry'
+import getNodeInterfaceType from './node/getNodeInterfaceType'
 import createCollectionQueryFieldEntries from './collection/createCollectionQueryFieldEntries'
 import BuildToken from './BuildToken'
 
+export const $$isQuery = Symbol('isQuery')
+
 // TODO: doc
 const getGQLQueryType = memoize1(createGQLQueryType)
 
 export default getGQLQueryType
 
 // TODO: doc
 function createGQLQueryType (buildToken: BuildToken): GraphQLObjectType<mixed> {
-  const { inventory } = buildToken
+  const { options, inventory } = buildToken
   let queryType: GraphQLObjectType<mixed>
 
-  queryType = new GraphQLObjectType({
+  queryType = new GraphQLObjectType<mixed>({
     name: 'Query',
     description: 'The root query type which gives access points into the data universe.',
+    interfaces: [getNodeInterfaceType(buildToken)],
+    // A value in our system is the value of this query type if there is no parent type
+    // (i.e. it is the root type), or the value is the symbol `$$isQuery`.
+    isTypeOf: (value, context, info) => info.parentType == null || value === $$isQuery,
     fields: () => buildObject<GraphQLFieldConfig<mixed, mixed>>(
       [
         createNodeFieldEntry(buildToken),
@@ -30,10 +37,19 @@ function createGQLQueryType (buildToken: BuildToken): GraphQLObjectType<mixed> {
         .map(collection => createCollectionQueryFieldEntries(buildToken, collection))
         .reduce((a, b) => a.concat(b), []),
       [
+        // The root query type is useful for Relay 1 as it limits what fields
+        // can be queried at the top level.
         ['query', {
           description: 'Exposes the root query type nested one level down. This is helpful for Relay 1 which can only query top level fields if they are in a particular form.',
           type: new GraphQLNonNull(queryType),
-          resolve: source => source || {},
+          resolve: source => $$isQuery,
+        }],
+        // The root query type needs to implement `Node` and have an id for
+        // Relay 1 mutations. This may be deprecated in the future.
+        [options.nodeIdFieldName, {
+          description: 'The root query type must be a `Node` to work well with Relay 1 mutations. This just resolves to `query`.',
+          type: new GraphQLNonNull(GraphQLID),
+          resolve: () => 'query',
         }],
       ],
     ),

src/graphql/schema/node/createNodeFieldEntry.ts

@@ -2,6 +2,7 @@ import { GraphQLFieldConfig, GraphQLNonNull, GraphQLID } from 'graphql'
 import { Collection, ObjectType } from '../../../interface'
 import { idSerde, scrib } from '../../utils'
 import BuildToken from '../BuildToken'
+import { $$isQuery } from '../getQueryGQLType'
 import getNodeInterfaceType from './getNodeInterfaceType'
 
 // TODO: doc
@@ -16,13 +17,19 @@ export default function createNodeFieldEntry (buildToken: BuildToken): [string,
         type: new GraphQLNonNull(GraphQLID),
       },
     },
-    async resolve (source: mixed, args: { [key: string]: mixed }, context: mixed): Promise<ObjectType.Value | null> {
+    async resolve (source: mixed, args: { [key: string]: mixed }, context: mixed): Promise<ObjectType.Value | Symbol | null> {
       let deserializationResult: { collection: Collection, keyValue: mixed }
       const idString = args[options.nodeIdFieldName]
 
       if (typeof idString !== 'string')
         throw new Error('ID argument must be a string.')
 
+      // If the id is simply `query`, we want to give back our root query type.
+      // For now this is needed for Relay 1 mutations, maybe deprecate this in
+      // the future?
+      if (idString === 'query')
+        return $$isQuery
+
       // Try to deserialize the id we got from our argument. If we fail to
       // deserialize the id, we should just return null and ignore the error.
       try {

src/postgraphql/__tests__/__snapshots__/postgraphqlIntegrationOperations-test.js.snap

@@ -1505,13 +1505,38 @@ Object {
 exports[`test operation query.graphql 1`] = `
 Object {
   "data": Object {
-    "node": null,
+    "__id": "query",
+    "a": null,
+    "b": Object {
+      "__id": "query",
+      "__typename": "Query",
+      "a": null,
+      "b": Object {
+        "__id": "query",
+        "__typename": "Query",
+      },
+    },
     "query": Object {
-      "node": null,
+      "__id": "query",
+      "a": null,
+      "b": Object {
+        "__id": "query",
+        "__typename": "Query",
+      },
       "query": Object {
-        "node": null,
+        "__id": "query",
+        "a": null,
+        "b": Object {
+          "__id": "query",
+          "__typename": "Query",
+        },
         "query": Object {
-          "node": null,
+          "__id": "query",
+          "a": null,
+          "b": Object {
+            "__id": "query",
+            "__typename": "Query",
+          },
         },
       },
     },

src/postgraphql/__tests__/__snapshots__/postgraphqlIntegrationSchema-information_schema-test.js.snap

@@ -2337,7 +2337,7 @@ input PgTypeInput {
 }
 
 # The root query type which gives access points into the data universe.
-type Query {
+type Query implements Node {
   # Fetches an object given its globally unique \`ID\`.
   node(
     # The globally unique \`ID\`.
@@ -4237,6 +4237,9 @@ type Query {
   # Exposes the root query type nested one level down. This is helpful for Relay 1
   # which can only query top level fields if they are in a particular form.
   query: Query!
+
+  # The root query type must be a \`Node\` to work well with Relay 1 mutations. This just resolves to \`query\`.
+  __id: ID!
 }
 
 type ReferentialConstraint {

src/postgraphql/__tests__/__snapshots__/postgraphqlIntegrationSchema-pg_catalog-test.js.snap

@@ -11745,7 +11745,7 @@ type PlpgsqlValidatorPayload {
 }
 
 # The root query type which gives access points into the data universe.
-type Query {
+type Query implements Node {
   # Fetches an object given its globally unique \`ID\`.
   node(
     # The globally unique \`ID\`.
@@ -20124,6 +20124,9 @@ type Query {
   # Exposes the root query type nested one level down. This is helpful for Relay 1
   # which can only query top level fields if they are in a particular form.
   query: Query!
+
+  # The root query type must be a \`Node\` to work well with Relay 1 mutations. This just resolves to \`query\`.
+  __id: ID!
 }
 
 input RandomInput {

src/postgraphql/__tests__/__snapshots__/postgraphqlIntegrationSchema-test.js.snap

@@ -426,7 +426,7 @@ type Post {
 }
 
 # The root query type which gives access points into the data universe.
-type Query {
+type Query implements Node {
   # Fetches an object given its globally unique \`ID\`.
   node(
     # The globally unique \`ID\`.
@@ -538,6 +538,9 @@ type Query {
   # Exposes the root query type nested one level down. This is helpful for Relay 1
   # which can only query top level fields if they are in a particular form.
   query: Query!
+
+  # The root query type must be a \`Node\` to work well with Relay 1 mutations. This just resolves to \`query\`.
+  id: ID!
 }
 
 input TableMutationInput {
@@ -956,7 +959,7 @@ type PageInfo {
 }
 
 # The root query type which gives access points into the data universe.
-type Query {
+type Query implements Node {
   # Fetches an object given its globally unique \`ID\`.
   node(
     # The globally unique \`ID\`.
@@ -1037,6 +1040,9 @@ type Query {
   # Exposes the root query type nested one level down. This is helpful for Relay 1
   # which can only query top level fields if they are in a particular form.
   query: Query!
+
+  # The root query type must be a \`Node\` to work well with Relay 1 mutations. This just resolves to \`query\`.
+  __id: ID!
 }
 
 # The exact time of day, does not include the date. May or may not have a timezone offset.
@@ -2288,7 +2294,7 @@ enum PostsOrderBy {
 }
 
 # The root query type which gives access points into the data universe.
-type Query {
+type Query implements Node {
   # Fetches an object given its globally unique \`ID\`.
   node(
     # The globally unique \`ID\`.
@@ -2552,6 +2558,9 @@ type Query {
   # Exposes the root query type nested one level down. This is helpful for Relay 1
   # which can only query top level fields if they are in a particular form.
   query: Query!
+
+  # The root query type must be a \`Node\` to work well with Relay 1 mutations. This just resolves to \`query\`.
+  __id: ID!
 }
 
 input TableMutationInput {

src/postgraphql/__tests__/fixtures/queries/query.graphql

@@ -9,10 +9,25 @@ query {
       }
     }
   }
+  a: node(__id: "hello") {
+    __typename
+    __id
+    ...query
+  }
+  b: node(__id: "query") {
+    __typename
+    __id
+    ...query
+  }
 }
 
 fragment query on Query {
-  node(__id: "hello") {
+  __id
+  a: node(__id: "hello") {
+    __typename
+    __id
+  }
+  b: node(__id: "query") {
     __typename
     __id
   }